Rescuers on Monday started their massive search operation on the Mandi-Pathankot highway near Kotropi village in Jogindernagar tehsil, 220 km from here, where two Himachal Road Transport Corporation buses, vehicles and several homes were washed away on Saturday night.

Meanwhile, most of the prominent tourist towns like Shimla, Narkanda, Kufri, Chail, Kasauli, Chamba, Dharamsala, Palampur and Manali have been witnessing good spells of rain for the past one week.

The water level in major rivers of the state - the Satluj, Beas and Yamuna - which enter the neighbouring states of Punjab and Haryana has been abnormally high, a government official said.

Shimla, which saw an overnight rain, recorded a low of 15.6 degrees Celsius on Monday.

Dharamsala - the seat of the Tibetan government-in-exile - saw a minimum of 17.6 degrees Celsius, while it was 13.6 degrees Celsius in Manali.

Local authorities have issued a word of caution for the holidaymakers.

"Make sure your trip is planned well in advance. Check on general road conditions and confirm whether the roads and high mountain passes are open," an official said.

The tourists are advised to carry light woollens as the temperatures in the hills have fallen sharply due to continuous rainfall.

Fearing landslide threat, the government has closed the road stretch between Mandi and Aut in Mandi district, located on the Chandigarh-Manali national highway. Local authorities have started route via Kalota to reach Kullu and Manali.

The Jogindernagar-Mandi section of the Pathankot-Mandi national highway has also been temporarily shut.